Railroad coil car structure

ABSTRACT

A transverse trough coil car has a sawtooth center sill. It has a pair of truck centers. Portions of the straight-through center sill deviate upwardly inboard of the truck centers and define saw teeth that have truncated tips. The center sill has an undulating top cover plate, or top flange. A portion of the center sill deviates slopingly to conform angularly to the inclined sides of the transverse troughs. The center sill is notched to conform to those transverse troughs. The car has stub bolsters that are surmounted by pre-fabricated trough assemblies that mate with the stub bolsters and extend to the side sills. The center sill has an array of internal web separators and gussets to discourage buckling. There are deep center sill webs that extend upwardly higher than the draft sill.

FIELD OF THE INVENTION

This invention relates to railroad freight cars, and more particularly to a railroad coil car.

BACKGROUND OF THE INVENTION

Railroad coil cars are used for carrying heavy coils of materials, quite often heavy coils of sheet steel such as are used in automobile manufacturing or other sheet metal manufacturing industries.

In a coil car, the coils can be carried with the axis of the coils parallel to the long axis of the railroad car. Such a coil car is termed a longitudinal coil car because it has a lengthwise running trough in which however many coils are carried. Such cars often have lateral coil stops to prevent the coils from moving axially in the trough. Alternatively, the coils can be transported with their axes oriented cross-wise to the long axis of the railroad car. In such a case, rather than having a single, central V-shaped trough running the length of the car, the coil car has several shorter troughs running across the car. Where the troughs run cross-wise, the railroad car is termed a “transverse trough coil car”.

It is not desirable for a heavy coil of steel to be free to roll during carriage in the well car. Coil cars are designed so that the weight of the lading coils is carried into the trough structure at points of tangency of the coil with the sloped sides of the trough. That is, the coil is effectively wedged between the sloped side sheets of the trough. This condition tends to prevent the coils from moving when the railroad car is in motion. The trough is designed such that the bottom of the trough has an included radius that is smaller than the lading coils for which the car is designed so that the points of tangency (or, really, given that the coils are cylindrical, the lines of tangency) lie on the sloped side sheets of the trough, not the bottom of the trough. When the coil sits in the trough, the bottom of the coil is suspended above the underlying structure at the bottom of the trough.

It may be that a coil of steel sheet may be relatively easily damaged by undesirably rough treatment during transport. Accordingly, coil cars may have long-travel draft gear or end of car cushioning units to soften deceleration. Where a coil car has a transverse trough, in addition to the structure for supporting the coils of lading during normal operation, there is also a requirement that the trough have a “trough peak” at either side of the car to discourage escapement of the coils in the event that the coil car should stop abruptly. The trough peak is not intended normally to be contacted by the coils, but only in an abnormal operating condition.

The floor structure may also include diagonal members to carry shear loads between the side beams.

SUMMARY OF THE INVENTION

In an aspect of the invention there is a transverse trough coil car having a sawtooth center sill.

In another aspect there is a transverse trough coil car having a pair of truck centers and a straight-through center sill in which at least a portion of said center sill deviates upwardly inboard of the truck centers.

In a further aspect there is a transverse trough coil car having a straight-through center sill in which the straight-through center sill has an undulating top cover plate.

In still another aspect, there is a transverse trough coil car having a center sill in which at least a portion of the center sill deviates slopingly to conform angularly to at least one inclined side of a transverse trough of said coil car.

In yet another aspect, there is a transverse coil car having a center sill that is notched to conform to at least one transverse trough of said coil car.

In still another aspect, there is a transverse trough coil car having at least a first trough and a second trough extending across the coil car. The first and second troughs each have a pair of first and second opposed slope sheets. The coil car has a straight-through center sill having a top cover plate. The coil car has at least one of: (a) slope sheets that terminate at an upward edge that conforms to the top cover plate; and (b) the first slope sheet of the first trough lies in a first plane, the second slope sheet of the second trough lies in a second plane. The first and second planes are upwardly inclined toward each other to intersect at a line of intersection above the center sill. The upper edge of the first slope sheet of the first trough and the corresponding upper edge of the second slope sheet of the second trough is truncated lower than the line of intersection.

It yet still a further aspect, there is a transverse trough coil car. It has a straight-through center sill and at least a first transverse trough. The first transverse trough has a convergent bottom and a divergent top. The center sill has a top cover plate. The bottom of the first trough lies at a height that is lower than at least a portion of the top cover plate of the straight-through center sill.

In a still further aspect, there is a transverse trough coil car having at least a first transverse trough. The first transverse trough has a pair of first and second opposed slope sheets that, in use, co-operate to define a cradle in which to receive lading. There are first and second trough peaks mounted to either side of the first transverse trough. The trough peaks have respective skirts oriented to face toward the first trough. The slope sheets are free of a shear connection to the respective skirts. In a feature of that aspect, the skirts of the trough peaks are more steeply inclined than the slope sheets.

In another aspect there is a transverse trough coil car having at least a first trough and a second trough, and a trough peak located between the first trough and the second trough, the first and second troughs having respective slope sheets. The slope sheets and the trough peak lack shear web continuity.

In yet another aspect, there is a transverse trough coil car having a stub bolster and a transverse trough mounted across the stub bolster. The transverse trough defines a bolster extension extending laterally across the car outboard of the stub bolster.

In a feature of those aspects, the coil car has a pair of truck centers and a straight-through center sill. At least a portion of the center sill deviates upwardly inboard of the truck centers. In another feature, the center sill has an undulating top cover plate. In still another feature, at least a portion of the center sill deviates slopingly to conform angularly to at least one inclined side of a transverse trough of the coil car. In still another feature, the center sill is notched to conform to at least one transverse trough of the coil car.

In still another feature, the coil car has at least a first trough and a second trough extending across the coil car. The first and second troughs each have a pair of first and second opposed slope sheets. The center sill is a straight-through center sill having a top cover plate. At least one of: (a) the slope sheets terminate at an upward edge that conforms to the top cover plate; and (b) the first slope sheet of the first trough lies in a first plane, the second slope sheet of the second trough lying in a second plane, the first and second planes is upwardly inclined toward each other to intersect at a line of intersection above the center sill. The upper edge of the first slope sheet of the first trough and a corresponding upper edge of the second slope sheet of the second trough are truncated lower than the line of intersection. In a further feature, there is a trough peak located between the first trough and the second trough. The slope sheets and the trough peak lack shear web continuity.

In yet another feature, the center sill is a fish-belly center sill. In another feature, the coil car has respective first and second draft sills. The center sill has those first and second draft sills at opposite ends thereof. The center sill has at least one tooth extending upwardly proud of the first and second draft sills. In another feature, the center sill has at least a first sawtooth located intermediate the first and second troughs. The first sawtooth has a truncated tip.

In another feature, the center sill has first and second spaced-apart side webs, and the side webs extend upwardly higher than the draft sills. In a further feature, there is web separator between the side webs. The web separator extends upwardly of the draft sills. In another feature, the first trough has first and second inclined, mutually opposed slope sheets defining tangent contact surfaces that, in operation, are engaged by lading coils. The first trough has a convergent bottom and a divergent top. The sawtooth center sill has at least a first sawtooth. The center sill has a top cover plate. A first portion of the top cover plate is located beneath the first trough. A second portion of the top cover plate is sloped and underlies the first slope sheet. In still another feature, the top cover plate has a third portion connected to the second portion and extending away from the first trough at a height corresponding to an upper margin of the first slope sheet. In yet another feature, the sawtooth center sill has draft sills mounted to opposed ends thereof, and the sawtooth center sill has a pair of first and second half teeth mounted at opposite ends thereof.

These and other aspects and features of the invention may be understood with reference to the illustrative drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the description that follows there is reference to the drawings in which:

FIG. 1 a is a general arrangement isometric view of a railroad coil car viewed from the “B” end of the car;

FIG. 1 b is a side view of the railroad coil car of FIG. 1 a;

FIG. 1 c is an enlarged detail of FIG. 1 b showing the location of section ‘6-6’;

FIG. 2 a is side view of the center sill of the coil car of FIG. la also showing the position of coils of lading in a set of transverse troughs;

FIG. 2 b is an enlarged detail of half the center sill of FIG. 2 a;

FIG. 3 a is an end view of the coil car of FIG. 1 a;

FIG. 3 b is a section in isometric view taken on section ‘3 b-3 b’ of FIG. 3 a;

FIG. 3 c is an enlargement of a first portion of FIG. 3 b;

FIG. 3 d is an enlargement of a second portion of FIG. 3 b;

FIG. 4 a is a perspective view of a transverse trough slope sheet sub-assembly of the railroad coil car of FIG. 1 a;

FIG. 4 b is a perspective view from below of the assembly coil car trough structure;

FIG. 5 is a perspective view from above and to one end of a trough peak assembly of the coil car of FIG. 1 a;

FIG. 6 is a sectional view on section ‘6-6’ of FIGS. 1 b and 1 c;

FIG. 7 a is a perspective view of the main bolster of the coil car of FIG. 1 a;

FIG. 7 b is an end view along the draft sill of the main bolster of FIG. 1 a; and

FIG. 7 c shows a view of the main bolster of FIG. 7 b on section ‘7 c-7 c’.

DETAILED DESCRIPTION

The description that follows, and the embodiments described therein, are provided by way of illustration of an example, or examples of particular embodiments of the principles, aspects or features of the present invention. These examples are provided for the purposes of explanation, and not of limitation, of those principles and of the invention. In the description, like parts are marked throughout the specification and the drawings with the same respective reference numerals. The drawings may be taken as being to scale unless noted otherwise.

The terminology in this specification is thought to conform to the customary and ordinary meanings of those terms as they would be understood by a person of ordinary skill in the railroad industry in North America. Following from decision of the CAFC in Phillips v. AWH Corp., the Applicant expressly excludes all interpretations that are inconsistent with this specification, and, in particular, expressly excludes any interpretation of the claims or the language used in this specification such as may be made in the USPTO, or in any other Patent Office, other than those interpretations for which express support can be demonstrated in this specification or in objective evidence of record in accordance with In re Lee, (for example, earlier publications by persons not employed by the USPTO or any other Patent Office), demonstrating how the terms are used and understood by persons of ordinary skill in the art, or by way of expert evidence of a person or persons of at least 10 years' experience in the industry in North America.

In terms of general orientation and direction, for railroad car body units described herein the longitudinal direction is defined as coincident with the rolling direction of the railroad car when on tangent (that is, straight) track. In a Cartesian frame of reference, this is the x-axis, or x-direction. The longitudinal direction is parallel to the center sill, and parallel to the top chords and side sills. Unless otherwise noted, vertical, or upward and downward, are terms that use top of rail, TOR, as a datum. In a Cartesian frame of reference, this may be defined as the z-axis, or z-direction. In the context of the railroad car as a whole, or any car body unit thereof, the term lateral, or laterally outboard, or transverse, or transversely outboard refer to a distance or orientation relative to the longitudinal centerline of the railroad car, or car body unit, or of the centerline of a centerplate at a truck center. Given that the railroad car or railroad car body units described herein may tend to have both longitudinal and transverse axes of symmetry, unless noted otherwise, a description of one half of the car may generally also be intended to describe the other half as well, allowing for differences between right-hand and left-hand parts. As such, the term “longitudinally inboard”, or “longitudinally outboard” is a distance taken relative to a mid-span lateral section of the car, or car unit. Pitching motion is angular motion of a railcar unit about a horizontal axis perpendicular to the longitudinal direction (i.e., rotation about an axis extending in the y-direction). Yawing is angular motion about a vertical or z-axis. Roll is angular motion about the longitudinal, or x-axis. The abbreviation kpsi, if used, stands for thousands of pounds per square inch. Where this specification or the accompanying illustrations may refer to standards of the Association of American Railroads (AAR), such as to AAR plate sizes or lading rules, those references are to be understood as at the earliest date of priority to which this application is entitled. Unless otherwise noted, it may be understood that the railroad cars described herein are of welded steel construction. The commonly used engineering terms “proud”, “flush” and “shy” may be used herein to denote items that, respectively, protrude beyond an adjacent element, are level with an adjacent element, or do not extend as far as an adjacent element, the terms corresponding conceptually to the conditions of “greater than”, “equal to” and “less than”.

Railroad coil cars are the predominant car type for carrying metal coils, and particularly coils of steel. The coil car may be covered or uncovered, depending on the circumstances. Cars for carrying transversely-oriented coils are described herein. The coil cars describe herein have a longitudinally running center sill and a pair of side sills located to either side of the center sill.

In the past, coil cars have had straight-through center sills that carry the longitudinal buff and draft loads to which the car is subjected, and also the vertical bending load. The center sill may have had a flat horizontal upper flange carried the full length of the car from draft sill to draft sill. Transverse troughs are then mounted above the center sill. In the past, coil cars have used “fish belly” center sills. The term “fish belly” arises from the shape of the beam in side view in which the bottom flange of the center plate dips downward between the trucks, giving a greater depth of section in the middle portion of the car, and hence a higher flexural moment EI for resisting bending, giving the general appearance of a “fish belly”.

In railroad terminology the “draft sill” is that portion of the center sill lying longitudinally outboard of the truck center. A single unit rail car typically has two draft sills, one at each end of the car. In some instances, e.g., where the draft sill is made as a unitary casting or as a pre-fabricated assembly, the draft sill extends inboard of the truck center for a short distance to allow for the draft sill to mate with the main portion of the center sill inboard of the truck center and inboard of the main bolster. The draft sill is typically sized to fit the draft gear. That is, the draft sill typically has two vertical webs that are laterally spaced apart a distance sufficient to form a draft pocket in which to mount the draft stops and to receive the draft gear, the yoke, and the coupler. The draft sill has a top cover plate, or top flange to which the webs are welded. The draft sill also typically has a bottom sill that extends outboard of the truck center and that bifurcates to permit the draft gear to be installed in the draft pocket. The top cover plate of the draft sill is usually considered to be the top of the center sill, and is located at a height determined by the requirements of the coupler centerline height. Generally, the top cover plate of the draft sill is located roughly 41″-42″ above Top of Rail. The flange defined by the top cover height of the draft sill is a defined datum height in this specification.

The term “stub bolster” is used in this specification. A stub bolster is a laterally fore-shortened bolster having a bottom flange, a top flange and at least one vertical web inter-connecting the top and bottom flanges. The bottom flange extends laterally to define a seat for the side bearing, and is truncated outboard of the side bearing mount. Likewise, the bolster web, or webs, terminate outboard of the side bearing mount. A stub bolster, by definition, does not extend to the side sills of the car.

FIGS. 1 a, 1 b and 1 c show a railroad coil car, generally as 20. Other than as indicated, the major structural elements of coil car 20 are symmetrical about the longitudinal vertical plane (or x-z plane) of the car and also about the lateral vertical plane. Coil car 20 has a railcar body unit 22 supported upon railcar trucks 24 for rolling motion in the longitudinal direction along the rails.

Railcar body unit 22 includes a center sill 26 and a pair of first and second, spaced apart side sills 28, 30. Coil car 20 has a set of troughs 32. In the example shown the troughs are transverse and include first, second, third, fourth and fifth troughs 34, 36, 38, 40 and 42. There could be fewer troughs, but there could also be more troughs, as many as ten or twelve, depending on the maximum size and type of coils of lading that the car is intended to carry. These troughs are supported by center sill 26 and extend between, and are bounded laterally by side sills 28 and 30. Between pairs of adjacent troughs there are trough peak assemblies, or simply “trough peaks”, 44 and at the ends of the car are end trough peak assemblies 46. Trough peak assemblies 44 are double-sided; trough peak assemblies 46 are single-sided.

These various components of coil car 20 will now be described in greater detail, commencing with center sill 26.

Center sill 26 is a straight-through center sill (as opposed to a stub center sill). It forms the central spine of the car and carries the buff and draft loads along the trainline from coupler to coupler. It is also provides the dominant resistance to vertical bending, although part of the car's resistance to vertical bending is also contributed by side sills 28 and 30. In the example shown, center sill 26 includes draft sills 48 and a central or intermediate center sill portion 50 that extends the length of the car between the truck from draft sill to draft sill. Draft gear, including couplers 52 are mounted at the outboard ends of draft sills 48. Coil car 20 may have, and in the example illustrated does have, either long-travel draft gear or and end-of-car-cushioning (EOCC) unit.

Each of draft sills 48 has a pair of side webs 54 and a top cover plate 56, and a bifurcated bottom flange, or flanges 58 that form a top hat section that is open from the bottom to admit installation of the EOCC in the draft pocket 60. Coupler 52 has a coupler centerline height h₅₂ relative to Top of Rail (TOR). The top cover plate of draft sill 48 also has a height, h₅₆, relative to TOR that is a datum height in this discussion. Draft sill 48 may have, and as illustrated does have, a welded-fabrication truck center assembly. This assembly, and the draft sill generally, may alternatively be a single-piece casting.

In the fabricated assembly of draft sill 48 shown, a main bolster 62 intersects draft sill 48 at the truck center. Main bolster 62 may be a bolster that extends fully across the car and has and connections to side sills 28, 30. Alternatively, main bolter may be, and in the example illustrated is, a stub bolster that terminates immediately outboard of the side bearing mount 64. This will be discussed in greater detail below.

A draft sill may include, and in the example illustrated does include, a transition, or stub 66 that extends for some distance longitudinally inboard of the truck center. Transition stub 66 mates with one end of central or intermediate center sill portion 50. In the example illustrated, side webs 68 of stub 66 of draft sill 48 have a “birds mouth” profile 67, namely a profile that is sinuous. This sinuous profile laps the end of the side web of intermediate portion 50 of center sill 26. The bird's mouth profile allows a longer weld fillet, and a higher proportion of a fillet in shear, than if these elements were butted together. In the example shown, the inboard end portion 70 of top cover plate 56 of draft sill 48 has been folded downward to form a web separator between webs 68.

Intermediate center sill portion 50 has a top cover plate 72, a bottom cover plate, or bottom flange 74, and first and second side webs 76, 78. They co-operate to form a hollow section in which side webs 76 and 78 are spaced apart and parallel, and lie in vertical planes. Similarly top cover plate 72 and bottom flange 74 are spaced apart, and at any given longitudinal section they are parallel in the y-axis.

Bottom flange 74 could be flat and horizontal. Alternatively, as seen in FIGS. 1 a, 1 b and 1 c , center sill 26 is a fish belly center sill, the deeper portion of the center sill that defines the fish belly as indicated at 75. Bottom flange 74 may be, and in the embodiment illustrated is, a “fish belly” bottom flange, i.e., the depth of the bottom flange below the coupler centerline datum height (or, expressed differently, the draft sill cover plate datum height) increases toward the longitudinal center of the car such that the bottom flange is lower at the location of maximum bending moment than it is at the truck centers and at the bottom flange of the draft sill.

As noted, the top cover plate is the same thing as the top flange of the center sill. Looking now at the top cover plate, it can be seen that a first portion 80 of top cover plate 72 of center sill 26 is at the datum height of the draft sill top cover plate at the truck center. First trough 34 and fifth trough 42 are centered over the respective truck centers at opposite ends of car 20. Both longitudinally inboard and longitudinally outboard of the truck center, center sill 26 has first and second inclined top cover plate portions 82 and 84 that ascend slopingly upward away from the truck center portion 80. Both outboard and inboard of these ascending portions are first and second level portions 86, 88 that join ascending portions 82, 84, respectively. First and second level portions 86, 88 of top cover plate 72 of center sill 26 are elevated relative to datum portion 80. First and second portions 82, 84 ascend at the angle of the slope sheets of the transverse trough at that longitudinal station of the car, namely first trough 34 or fifth trough 42. Moving inboard, this pattern is repeated for second trough 36 and fourth trough 40, which has a bottom portion 90 of top cover plate 72 that is located between a pair of first and second ascending portions 92, 94. The first ascending portion 92 of second trough 36 is joined to second level portion 88. Ascending portion 94 mates with corresponding second level portion 88, and bottom portion 90. Finally, in respect of third trough 38, top cover plate 72 of center sill 26 similarly has a bottom portion 100 bracketed by ascending portions 98 that mate with the respective adjacent one of elevated level portions 96, to either side of middle trough 38. It may be noted that, in context, an ascending portion is also a descending portion when viewed from the opposite perspective. It follows that the top cover plate 72 can be said to undulate from a low portion in the bottom of one trough, a rising portion running up one side, a plateau or level portion running between two troughs, a descending portion running into the next trough, where there is another bottom portion, and so on, repetitively, to the other end of the car.

It can be seen that the resultant center sill, when seen in side view as in FIG. 1 b , has a “sawtooth” profile of successive upwardly pointing teeth, such that center sill intermediate portion 50, and accordingly center sill 26 more generally, is a “sawtooth center sill”. In this case, a first sawtooth 35 is defined between trough 34 and trough 36; a second sawtooth 37 is defined between trough 36 and trough 38; a third sawtooth 39 is defined between trough 38 and trough 40; and a fourth sawtooth 41 is defined between trough 40 and trough 42. There are also two additional “sawteeth”, or half-“sawteeth” 33 and 43 at the longitudinal ends of the set of troughs. In the example shown, there are four such sawteeth (35, 37, 39 and 41) and two such half teeth (33, 43). To the extent that the upper flange of the center sill may be seen as a repeating wave form, there is a period, or wavelength, or cycle, from the center of one low point to the next low point (or, equivalently, from one high point to the next high point). It may also be noted that in the embodiment illustrated the teeth are truncated teeth, in which the point of the tooth is flattened. This can be expressed differently. That is, the ascending (or descending, depending on the point of view) portions on either side of each “tooth” lie in respective planes. Those planes, projected along their slope, meet at a line of intersection. However, the upper margins of the sloped portions of the sides of the tooth are truncated short of the line of intersection at a lower height. It is not necessary that all of the low portions of the center sill top cover plate be carried at the same height, some, such as the longitudinally centermost could be carried at a higher height for use with smaller coils. It is also possible that some troughs could be smaller and narrower than others, for use with smaller coils. However, it is convenient that all of the troughs be the same size, and that the top flange portions of the center sill forming the bottoms of the respective troughs be carried at the same height, that datum height being the same as the height of the top cover plate over the truck center. The higher level portions also do not need to be carried at the same height, or to be planar, or to be level. However, as in the illustration shown, it is convenient that they be of the same height, and that they be level. Further, although it need not be so, it is convenient for the upper height to correspond to the height of the top chord of the respective side sills 28, 30. The result is an undulating, or sinuous, or alternately ascending and descending center sill top flange. As indicated, part of the top flange of the center sill is at a different height from another part. Part of the top cover plate is inclined on a slope in the longitudinal direction.

Given that the top flange of the center sill varies in height, side webs 76, 78 also have varying vertical depth, a lower margin that conforms to the fish belly profile and an upper margin that conforms to the sawtooth profile, i.e., the profile of the top flange of center sill 26. That is, side webs 76, 78 have respective first portions 102 in which the upper margin of the web is at the level of the top cover plate at the truck center. It has other, taller, portions 104 at which the upper margin is at a higher level, such as conforms to the level of the raised portions of the center sill top flange, generally corresponding to the shape of the top end of one of the teeth of the sawtooth profile and the corresponding portion of the center sill top flange. Side webs 76, 78 further include intermediate portions 106, 108 that have angled top margins to conform to the angle of the various slope side sheets of the various troughs. In the case of portions 104, 106, and 108, part of the portion extends upwardly proud of the datum height h₈₀ of the center sill top flange over the truck center. Side webs 76, 78 may each have a lower part 110 that has a lower edge having a profile conforming to the profile of the fish belly, and an upper edge that is straight or substantially straight running at the level of the underside of the top cover plate at the truck center. It may also include, and in the embodiment illustrated does include, a set of upper part 112 that have an upper edge shaped to conform to one or another of the teeth of the respective sawtooth, and a lower margin that conforms to the upper margin of lower part 110. That lower margin may be, and as illustrated is, a straight edge. In the example illustrated, each upper part 112 has a trapezoidal shape in which the top and bottom edges are parallel and the other two edges are angled equally in opposite directions to conform to the angel of the slope of the sides of the troughs. Upper part 112 may be butt welded to lower part 110. A lap weld may also be made, with or without a backing bar. The profile of upper portion 112 defines the sawtooth shape.

Considering the views of FIGS. 3 b, 3 c and 3 d , and also of FIGS. 4 a and 4 b , intermediate portion 50 of center sill 26 includes a set of web separators, i.e., laterally extending webs that hold the lateral spaced apart relationship of webs 76, 78 relative to each other. That is, there is an upper web separator 114. There could be more than one such separator. In the embodiment illustrated, in each tooth of teeth 35, 37, 39 and 41 of the sawtooth center sill there is a single upper web separator 114 spaced centrally in the respective tooth, located in a vertical plane. It extends downward from the underside of the vertically truncated flat portion of the top cover plate to a level corresponding to the datum height of the top cover plate at the truck center, and may have rounded transition fingers that extend below that height.

There are additional web separators 118 and 120 that are positioned to either side of the central web separator of the central tooth. They radiate away from the junction of the respective low top cover portion 100 of third trough 38, and the ascending portions 98 of top cover plate 72 corresponding to the sloped sides of adjacent teeth 37, 39. The angle of inclination of web separators 118 and 120 is such that they angle downwardly from the horizontal at a steeper angle than the slope sheet angles upwardly. Web separators 118 and 120 terminate at a respective bottom flange close to but spaced away from, and roughly parallel to, the bottom flange 74 of center sill 26. As before, there are external gussets 122, 124 to either side of center sill 26. As shown, gussets 122, 124 are triangular. They are positioned to be aligned in web continuity with web separators 118, 120, as may be, and may typically be co-planar with those web separators. They have a vertical edge that mates with the outside face of the respective on of webs 76, 78. They have a horizontal edge running in the y-direction that mates with the junction of the bottom and slope sheet of the adjacent trough assembly. Web separators 118 and 120 (and therefore also gussets 122, 124) of the central, or third, trough 38 are positioned at equal and opposite angles relative to the mid span z-y plane of the car center line.

Moving longitudinally outboard in either direction from third trough 38 to second and fourth troughs 36 and 40, there are web separators 126 that extend downwardly away from the junction of bottom level portion 90 and inclined portions 94 of top flange of top cover plate 72. As before, there are external gussets 128 associated with web separators 126 mounted to the outside of webs 76, 78 in the plane of web separator 126 that provide web continuity, and resistance to buckling.

Similarly there is a web separator 130 and corresponding outside gussets 132 that extend downwardly away from the junction of level bottom portion of part 90 and inclined portion 94 of top cover plate 72. As before, web separator 130 and gussets 132 are coplanar and perpendicular to webs 76, 78. In this case, however, the angle of inclination of the respective planes of web separator 126 and web separator 130 are not the same in angular magnitude relative to vertical. Rather, web separator 126 is more steeply inclined than web separator 130.

As can be seen in FIG. 3 d , there is a transition from the deepest portion of the fish belly to the draft sill. In that regard bottom flange 74 has a central part 134 that is flat and horizontal that defines the lowest, or deepest, part of center sill 26. There is a slopped transition part 136 that extends between central part 134 and bottom flange 58 of draft sill 48. At each junction there is a backing plate 138 permitting the two portions to be butt welded, and to be lapped by the backing plate. At the juncture of central part 134 and transition part 136 not only is there backing plate 138 but also another internal web separator 140 that extends upwardly from that joint. The inboard end 70 of top cover plate 56 is bent downwardly to define yet another web separator 142. There are two additional vertical transverse webs 144 and 146 inside draft sill 48 bracketing the Truck Center, and forming the fore and aft walls of the center plate accommodation in which center plate casting 148 locates. Webs 144 and 146 are substantially coplanar with, and provide web continuity with, the corresponding webs 234 and 236 of main bolster 62.

The next structural components of the underframe of coil car 20 are side sills 28 and 30. Side sills 28 and 30 each have a top chord 150, a bottom chord 152 and a web 154 that extends and joins top chord 150 and bottom chord 152 together. In the illustrations, top chord 150, bottom chord 152, and web 154 are formed as a single formed section, which may be a pressing. The pressing may include an upwardly protruding, longitudinally extending stand-off bead 156 formed in top chord 150.

Center sill 26 and side sills 28, 30 form the dominant structural members of the underframe of coil car 20. The center sill and side sills are joined by lateral structural members. In car 20 there are also lateral structural members joining center sill 26 to side sills 28 and 30. There are end sills 158 at either end of the car, and laterally extending stub walls 220. There are lateral catwalks 240 that run across the end of car 20 inboard of end sill 158 and stub wall 220. The major lateral structural connection along the car is provided by the transverse trough assemblies 160 of troughs 34 to 42.

A perspective view of a transverse trough assembly 160 is shown in FIG. 4 a . Trough assembly 160 can be assembled as a pre-assembled module during manufacture, for subsequent mating with the underframe of car 20, e.g., center sill 26 and side sills 28, 30. Trough assembly 160 may be used in each of the first, second, third, fourth and fifth troughs. Each assembly 160 as illustrated includes a pair of slope sheets 162, 164, a lateral top sheet 166, trough bottoms 168 and longitudinally extending reinforcement 170. Internal reinforcement 170, which may itself be an assembly, may be thought of as a form or frame, or as a stringer that runs longitudinally at a lateral location intermediate center sill 26 and side sills 28, 30.

Starting from the bottom of the trough, trough bottom 168 may have, and in the example illustrated does have, the form of a pan or tray, or shallow channel that has a central portion 172 and a pair of margins 174, 176. Central portion 172 may have the form of a flat plate that is planar, and, as installed, is level and runs horizontally. Margins 174, 176 are bent upwardly to form a lip. The lip may be, and as illustrated is, bent on an angle to conform to the mating slope of the respective slope sheet 162, 164. On assembly, the lip permits formation of a lap joint that can be welded inside and out.

Next, reinforcement 170 has a principal member in the form of a member that is a plate or web 180 that, as shown, as the form of a trapezoid that is broad at the bottom and narrow at the tip, with the inclined edges of the trapezoid conforming to the profile of slope sheets 162, 164. It has a base flange 178 and inclined slope flanges 182, 184. Base flange 178 runs along the long bottom edge of the trapezoid, and has toes 186 that extend beyond the ends of the trapezoid to locate under, and to be welded to, the bottom side of the pan of trough bottom 168. Flanges 182, 184 are bent from web 180 to lie parallel to the slope sheets, and to provide a broader attachment with weld fillets on both long edges of the flange to the slope sheet, in a manner tending to spread the loading stress in the plate to the flange. The top edge of web 180 is welded to lateral top sheet 166. Slope sheets 162, 164 have bent margins 188 that lap over the edges of lateral top sheet 166. As may be noted, each tough assembly 160 has a pair of trough bottoms 168 that are spaced apart on the axis of the trough, such that tough bottoms 168 bracket, and mate with, top flange or top cover plate 72 of center sill 26.

Slope sheets 162, 164 are continuous from side to side of the car body, and overlie, and are welded to both lateral margins of the ascending portions of top flange 72 of center sill 26. On the laterally outboard edge, sloped sheets 162, 164 mate with respective webs 154 of side sills 28, 30. Similarly, top sheet 166 is welded along both lateral running edges of the adjacent slope sheets and along both lengthwise running edges to the respective flat portion of the center sill top chord, and to the top chord of the side sill. That is, top sheet 166 is a shear plate that extends in a plane that corresponds to the plane of the top chord of the side sill and the raised flat portions of the top cover plate of the center sill. That is, coil car 20 is a transverse trough coil car having a center sill, a pair of side sills spaced apart from said center sill, and a set of troughs running across said car, said center sill having a top cover plate, said top cover plate having a portion that is substantially flush with corresponding top chords of said side sills. In such a car, the additional center sill depth, overall, may tend to permit somewhat less reliance to be place on the side sills to aid in resistance to vertical bending. As such, the top chords of the side sills may be at substantially flush with the truncated tops of the sawteeth.

Trough peak assemblies 44 are located between each pair of adjacent troughs. They include a roof or hat 190, a pair of end plates 192, and a set of internal webs 194. The roof or hat may be a bent single sheet that forms the roof peak 196 and has a pair of side sheets, or skirts 198. While internal webs have a generally triangular shape, they are not exactly triangular. That is, the angled side edges 200, 202 have a lower portion 204 that is generally angled on the slope of slope sheets 162, 164, and an upper portion 206 that extends on a steeper, sharper angle. The result is an edge that has an inward knee or inward dog-leg 208. Skirts 198 extend along the slope of the upper angle. Skirts 198 end at the slope discontinuity defined by the inward knee 208. There is a space between the lower margin of skirt 198 and the upper margin of slope sheets 162, 164 such that there is no shear web continuity between skirts 198 and slope sheets 162, 164. End plates 192 are triangular and slightly larger than webs 194, such that they cap the respective outboard ends of skirts 198. The bottom portion of end plates 192 forms a generally rectangular foot or tab 228 that laps the upper margin of web 154 of side sill 28, 30 and is welded thereto. Lateral top sheet 166 then welds to end plate 192 and thereby obtains the continuity of web connection to side sill 28, 30. The trough peak extends to a height higher than the side sills and defines a raised retainment barrier for the lading.

One sided trough peak assemblies 46 are of substantially the same structure as trough peaks 44, except that they are one-sided. That is, they have a roof or hat or cap 210 that may be formed from a bent sheet to form the ridge cap that has an inboard web or skirt 212 and an outboard leg 214. There are internal webs 216 and end caps 218. Internal webs 216 have one side that has the same dog-leg profile as webs 194. Outboard leg 214 follows the contour of the outboard edge of webs 216 and terminates at the upper edge of a lateral stub wall 220 that runs across the end of car 20 from the end of side sill 28 to the end of side sill 30. There are webs 222 that lie in the respective planes of webs 54 of draft sill 48 and support the inclined slope sheet support and center sill top flange extension horizontal flange portion 86, and consequently lateral cover plate 226 (the half-peak analogue of top sheet 166) that extends across car 20 from top chord to top chord of side sills 28, 30. Accordingly, the structure defines a continuous stub wall at the end of car 20. As before, the trough facing skirt, namely skirt 212, is mounted with a gap between its lowermost margin and the uppermost margin of the nearest slope sheet 162, 164 such that there is not shear web continuity between the skirt and the slope sheet.

First trough 34 and last trough 42 are centered on the respective truck centers. As seen in FIGS. 7 a, 7 b and 7 c , there is a stub bolster 230. It has a bottom flange 232, a pair of vertical webs 234, 236 spaced apart from each other and that stand upwardly from bottom flange 232. At the location of the truck centers, the top flange of center sill 26 is broadened locally. At these locations, the respective trough bottoms 168 are welded to the upper margins of webs 234, 236. Vertical webs 234, 236 and bottom flange 232 terminate laterally outboard of the side bearing mount. From that point to side sill 28, 30, trough 34 and trough 42 function as the lateral bolsters of the car. That is, trough bottom 168 forms the flange of the bottom of a channel, and slope sheets 162, 164 form the legs of that channel, with that hybrid channel performing the role of the main bolster.

In summary, there is a transverse trough coil car 20 having a sawtooth center sill 26. The transverse trough coil car 20 has a pair of truck centers. Center sill 26 is a straight-through center sill in which portions of center sill 26 deviate upwardly inboard of the truck centers, namely as saw teeth 33, 35, 37 and 39. Straight-through center sill 26 has an undulating top cover plate, of top flange, 72. A portion of center sill 26, namely inclined portions 82, 84, 92, 94 and 98, deviate slopingly to conform angularly to the inclined sides, namely slope sheets 162, 164 of the transverse troughs 34, 36, 38, 40, and 42 of coil car 20. As seen in profile view in FIGS. 2 a and 2 b , center sill 26 is notched to conform to those transverse troughs.

Troughs 34, 36, 38, 40, and 42 extend across coil car 20. Each trough has a pair of first and second opposed slope sheets 162, 164. Center sill 26 has a top cover plate, or top flange, 72. Slope sheets 162, 164 terminate at respective upward edges that conforms to top cover plate 72. Slope sheet 162 of trough 34 (or 42) lies in a first plane. Second slope sheet 164 of trough 36 (or 40) lies in a second plane. The first and second planes are upwardly inclined toward each other, such that when projected they intersect at a notional line of intersection above the center sill. The upper edge of slope sheet 162 and a corresponding upper edge of slope sheet 164 are truncated lower than the line of intersection. The troughs have a convergent bottom and a divergent top. The bottom of the trough lies at a height that is lower than the portion of the top cover plate that is raised upwardly on the upper tips of the respective saw-teeth. Opposed slope sheets 162, 164, in use, co-operate to define a cradle in which to receive lading. First and second trough peaks 44 (or 44 and 46) mounted to either side of the respective transverse trough have respective skirts 198 (or 212) oriented to face toward the respective trough. Those slope sheets 162, 164 are free of a shear connection to the respective skirts 198, 212. Skirts 198, 212 of trough peaks 44, 46 are more steeply inclined than are slope sheets 162, 164.

Coil car 20 has a stub bolster 230 and transverse troughs 34, 42 mounted across the stub bolster 230. Transverse troughs 34, 42 define bolster extensions that extending laterally across the car outboard of the stub bolster to the side sills.

Coil car 20 has a center sill 26 that has draft sills 48 at opposite ends thereof. Center sill 26 has saw teeth 33, 35, 37, 39, 41 and 43 that extend, or stand, upwardly proud of draft sills 48. Saw teeth 35, 37, 39 and 41 are each located intermediate a pair of troughs. Saw teeth 33, 35, 37, 39, 41 and 43 have truncated tips. Center sill 26 has first and second spaced-apart side webs 76, 78. Webs 76, 78 extend upwardly higher than draft sills 48. There is a web separator 114 that extends upwardly of the datum height defined by the height of the top cover plate 56 of draft sills 48.

The surfaces of slope sheets 162, 164 are inclined and mutually opposed. They define tangent contact surfaces that, in use, are engaged by lading coils. Top cover plate 72 has a first portion 80 defining a datum height, a second portion 84 that extends on a slope upwardly of the datum height, and a third, level portion 88 connected to the second portion and that extends away from the first trough 34 at a height corresponding to an upper margin of first slope sheet 162 (or 164, as may be). Center sill 26 has a pair of first and second half teeth 33, 43 mounted on top of draft sills 48 that define the opposite ends of center sill 26.

It can likewise be said that there is a transverse trough coil car that has a pair of truck centers and a straight-through center sill in which at least a portion of said center sill deviates upwardly inboard of the truck centers. Seen in another way, there is a transverse trough coil car that has a straight-through center sill in which said straight-through center sill has an undulating top cover plate. Alternatively, there is a transverse trough coil car having a center sill in which at least a portion of the center sill deviates slopingly to conform angularly to at least one inclined side of a transverse trough of said coil car. In still another way the description has shown a transverse coil car having a center sill that is notched to conform to at least one transverse trough of said coil car.

Coil car 20 is a transverse trough coil car having first and second troughs extending thereacross. Each of the first and second troughs has a pair of first and second opposed slope sheets. There is a straight-through center sill having a top cover plate. The slope sheets terminate at an upward edge that conforms to the top cover plate. The first slope sheet of the first trough lies in a first plane. The second slope sheet of the second trough lying in a second plane. The first and second planes are upwardly inclined toward each other to intersect at a line of intersection above said center sill. An upper edge of the first slope sheet of the first trough and a corresponding upper edge of the second slope sheet of the second trough are truncated lower than that line of intersection.

Coil car 20 is a transverse trough coil car having a straight-through center sill and at least a first transverse trough having a convergent bottom and a divergent top. The center sill has a top cover plate. The bottom of the first trough lies at a height that is lower than at least a portion of the top cover plate of the straight-through center sill. Coil car 20 is a transverse trough coil car having a center sill, a pair of side sills spaced apart from said center sill, and a set of troughs running across said car. The center sill has a top cover plate. The top cover plate has a portion substantially flush with corresponding top chords of the side sills. Coil car 20 is a transverse trough coil car having a set of transverse troughs that includes at least a first transverse trough. The first transverse trough has a pair of first and second opposed slope sheets that, in use, co-operate to define a cradle in which to receive lading. The first and second trough peaks are mounted to either side of the first transverse trough. The trough peaks have respective skirts oriented to face toward the first trough. The slope sheets are free of a shear connection to the respective skirts. The skirts of the trough peaks are more steeply inclined than the slope sheets.

Coil car 20 is a transverse trough coil car having a stub bolster and a transverse trough mounted across the stub bolster. The transverse trough defines a bolster extension that extends laterally across the car outboard of the stub bolster. Coil car 20 is a transverse trough coil car having at least a first trough and a second trough, and a trough peak located therebetween. The first and second troughs having respective slope sheets. The slope sheets and trough peaks lack shear web continuity between them.

However expressed, coil car 20 has a center sill. Coil car 20 has a pair of truck centers and a straight-through center sill. At least a portion of the center sill deviates upwardly inboard of the truck centers. The center sill has an undulating top cover plate. At least a portion of the center sill deviates slopingly to conform angularly to at least one inclined side of a transverse trough of said coil car. The center sill is notched to conform to at least one transverse trough of the coil car. The center sill is a fish-belly center sill. The center sill has first and second draft sills at opposite ends thereof. The center sill includes at least one sawtooth extending upwardly proud of the first and second draft sills. The Sawtooth is located intermediate the first and second troughs. The sawtooth has a truncated tip. The center sill has first and second spaced-apart side webs that extend upwardly higher than the draft sills. The center sill has a pair of side webs and at least a first web separator located between the side webs. The web separator extends upwardly of the draft sills.

The troughs have first and second inclined, mutually opposed slope sheets defining tangent contact surfaces that, in operation, are engaged by lading coils. The troughs have respective convergent bottoms and divergent tops. The center sill has at least a first sawtooth. The center sill has a top cover plate. A first portion of the top cover plate is located beneath the first trough. A second portion of the top cover plate is sloped and underlies the first slope sheet. The top cover plate has a third portion connected to the second portion of the top cover plate. The third portion extends away from the first trough at a height that corresponds to an upper margin of the first slope sheet. The center sill has draft sills mounted to opposed ends thereof, and said center sill has a pair of first and second half teeth mounted at opposite ends thereof above the ends of the draft sills.

In earlier transverse trough coil cars, the trough structure adds some stiffness to the center sill. When these stiffer sections of the center sill are considered as part of the overall beam stiffness, it creates changing sectional properties along the length of the car. The changes in stiffness are associated with stress concentrations in the center sill at the start and termination of the respective trough structures. The stress concentrations manifest themselves under various loading conditions, but, overall, tend to reduce the structural integrity of the car and to give rise to fatigue failure initiation sites. The design as described herein recognizes these phenomena, and integrates the trough mounds in the center sill to benefit from the additional sectional properties while paying attention to the corner stresses and providing a continuous load path in the top flange and providing additional stiffeners in the corners. This permits a comparatively direct load path from the coils to the center sill as the vertical force of the coils transfers into the center sill webs. By using the various component features for multiple purposes it may tend also to reduce the number of components and the welding required.

In this disclosure there is a transverse-trough coil car with a sawtooth center sill assembly. It has trough peaks and a bolster assembly. The center sill assembly differs from standard through-sill railcars. Center sills generally have a uniform cross-section along the length, with some featuring a fish belly design toward the middle of the car for increased bending stiffness. In transverse coil cars, the troughs are typically built-up structures that sit on and are attached to the top of the center sill. The troughs are supported on their ends by the side sills. The coil car described here is a design that combines the trough structure with the center sill. It has been done by fabricating a center sill assembly with the top of the center sill having a sawtooth profile, as illustrated in FIGS. 1 b and 3 b. The top flange of the center sill is fabricated to create a continuous load path from each end of the center sill, following the contours of the trough shapes. The webs are shaped accordingly. The tops of the peaks only extend partially as required and sufficient to provide the tangential bearing surface suited to receive the largest coil to be accommodated in the trough; and to have tops that remain flat between the troughs in a regular beam-like geometry.

In respect of trough peaks, the embodiments described herein effectively eliminate a traditional trough peak defined at the intersection of the planes of mutually inclined slope sheets of adjacent troughs. In the example described, the slope sheets defining the tangent slopes contacted by the lading coils terminate, and a trough peak assembly is added that has skirts that are not co-planar with the trough slope sheets, but rather have skirts that are oriented at a steeper angle than the slope sheets.

The function of the trough peak is to discourage or to prevent coils from rolling out of the troughs due to longitudinal forces, primarily from impact. The AAR Open Top Loading Rules have governing dimensions for railcars with troughs for carrying coiled steel, one of which advises the presence of a trough peak through a prescribed minimum height based on coil size. This requirement states that the height of the trough must extend at least 4 inches up-slope beyond the contact point with the coil. The slope sheets must extend past a point that would engage 30% of the height of the coil diameter, and the slope of the tangent sheets must be at least 35 degrees. The overall height of the trough peak must be at least 50% of the coil diameter, or, conversely, the coil lading cannot be larger than twice the height of the trough peak. In past cars, generally, the trough peak has been an extension of the trough, such that the peak is continuous with the trough sheet and the trough peak lies in the plane of the slope sheet (and at the line of intersection of the planes of the slope sheets of two adjacent troughs.

The design described introduces a discontinuous trough surface. The trough as-a-whole coil-carrying compartment has two separate component assemblies, namely (a) a trough loading surface for carrying the coils; and (b) a trough peak assembly that satisfies the AAR requirement to act as a barrier to excessive longitudinal rolling of coils. In ordinary use coils are not expected to roll during transport, and any such rolling may result in the rejection of the coil by the end user. The trough peak is a separate assembly affixed to the flat mound (i.e., the truncated top of a respective one of the sawteeth) between trough valleys. The coil-carrying trough surface (or lower portion of the trough compartment) follows the sawtooth contours of the center sill top flange components to create a continuous planar surface between the side sills, being in essence a lateral projection (or pair of lateral projections) of the center sill top surface to the side sills.

The trough peak assembly has multiple aligned triangular (or generally triangular) plates with an upside-down v-shaped sheet laid over the edges of the triangular plates that only covers the upper, coil-contacting upper part of the peak, and that exposes the bottom portion of the aligned plates. The alignment of the plates with the center sill webs and with other underlying structural members in the same plane allows the peak to have substantial stiffness to bear the longitudinal forces of coil impact and to resist high moment forces through securement to structural members. These trough peak assemblies can be attached to the car by welding to the top of the lower trough surface, creating a continuous load path or affixed through some other method (bolted, riveted), to allow engagement with the underlying structure to obtain rigidity. Providing a separate trough peak assembly may tend to simplify assembly. The minimalist approach of the example herein may tend to use less material and to facilitate manufacture. The trough peaks can be assembled separately and then joined to the trough mounds. The design then has a shallower slope angle at the coil carrier contact, and trough peaks of a steeper angle.

In respect of the bolster, the example described herein uses a new method of manufacture. Bolsters are a short beam, typically a fabricated box-beam or I-beam with the main function of resisting torsion and resisting lean of the car body through the side bearings. If often, if not always, also functions as a cross-bearer. For both of these functions, the bolster acts as a rigid arm extension of the center plate. The bolster described herein combines the flat-bottomed valley of the trough and the top flange of the bolster, eliminating the need for a bolster top cover. The bolster webs are welded to the flat portion of the trough sheet, forming a box section. This differs from the traditional bolster by integrating the trough and the bolster structure, as shown in the Figures. The structural properties of the trough sheets permit the bolster to be a stub bolster, as shown and described, i.e., that does not require a full-length box beam structure extending fully laterally outboard to mate with the side sills.

This approach may tend to make manufacture easier, and to reduce the amount of material used. The geometry of the trough sheet at the bolster location is a large, wide, flat-bottomed V-shape. This geometry, by itself, has a large second moment of area, reducing dependence on the bolster for stiffness in transferring side bearing loads to the center sill and carrying the side sill. By using the natural beam-like properties of the trough sheet and its geometry, the bolster can be reduced to a stub-bolster that bears the side bearing loads, and a trough sheet that performs the beam function customarily provided by a traditional bolster. In the example, the bolster top flange is partially or wholly eliminated relative to standard designs.

Various embodiments have been described in detail. Since changes in and or additions to the above-described examples may be made without departing from the nature, spirit or scope of the invention, the invention is not to be limited to those details but only by a purposive reading of the claims as required by law. As may be understood without further multiplication and repetition of description, the various features of the several embodiments may be mixed and matched as appropriate. 

What is claimed is:
 1. A transverse trough coil car having a sawtooth center sill.
 2. The transverse trough coil car of claim 1 wherein said transverse trough coil car having a pair of truck centers and a straight-through center sill; and at least a portion of said center sill deviates upwardly inboard of the truck centers.
 3. The transverse trough coil car of claim 1 wherein said sawtooth center sill has an undulating top cover plate.
 4. The transverse trough coil car of claim 1 wherein at least a portion of said center sill deviates slopingly to conform angularly to at least one sloped side of a transverse trough.
 5. The transverse trough coil car of claim 1 wherein said sawtooth center sill is notched to conform to at least one transverse trough of said coil car.
 6. The transverse trough coil car of claim 1 wherein: said coil car has at least first and second troughs extending thereacross; said first and second troughs each have a pair of first and second opposed slope sheets; said sawtooth center sill is a straight-through center sill having a top cover plate; and at least one of: (a) said slope sheets terminate at an upward edge conforming to said top cover plate; and (b) said first slope sheet of said first trough lies in a first plane; said second slope sheet of said second trough lying in a second plane, said first and second planes being upwardly inclined toward each other to intersect at a line of intersection above said center sill; and an upper edge of said first slope sheet and a corresponding upper edge of said second slope sheet being truncated lower than said line of intersection.
 7. The transverse trough coil car of claim 1 having at least first and second troughs, and a trough peak located therebetween, said first and second troughs having respective slope sheets; and said slope sheets and said trough peak lack shear web continuity.
 8. The transverse trough coil car of claim 1 wherein said sawtooth center sill is also a fish-belly center sill.
 9. The transverse trough coil car of claim 1 wherein said coil car has respective first and second draft sills; said sawtooth center sill has said first and second draft sills at opposite ends thereof; and said sawtooth center sill includes at least one tooth extending upwardly proud of said first and second draft sills.
 10. The transverse trough coil car of claim 9 wherein said sawtooth center sill includes first and second spaced-apart side webs that extend upwardly higher than said draft sills.
 11. The transverse trough coil car of claim 10 wherein there is web separator between said side webs, said web separator extending upwardly of said draft sills.
 12. The transverse trough coil car of claim 1 wherein said coil car has at least first and second troughs; said sawtooth center sill includes at least a first sawtooth located intermediate said first and second troughs; and said first sawtooth has a truncated tip.
 13. The transverse trough coil car of claim 1 wherein said coil car includes at least a first trough; said trough has first and second slope sheets, said first and second sloped sheets being mutually opposed and inclined, and defining tangent contact surfaces that, in operation, are engaged by lading coils; said first trough has a convergent bottom and a divergent top; said sawtooth center sill includes at least a first sawtooth; said center sill has a top cover plate; a first portion of said top cover plate is located beneath said first trough; and a second portion of said top cover plate is sloped and underlies said first slope sheet.
 14. The transverse trough coil car of claim 13 wherein said top cover plate includes a third portion connected to said second portion and extending away from said first trough at a height corresponding to an upper margin of said first slope sheet.
 15. The transverse trough coil car of claim 1 wherein said sawtooth center sill has draft sills mounted to opposed ends thereof, and said sawtooth center sill has a pair of first and second half teeth mounted at opposite ends thereof.
 16. A transverse trough coil car having a pair of truck centers and a straight-through center sill in which at least a portion of said center sill deviates upwardly inboard of the truck centers.
 17. A transverse trough coil car having a straight-through center sill in which said straight-through center sill has an undulating top cover plate.
 18. A transverse trough coil car having a center sill in which at least a portion of the center sill deviates slopingly to conform angularly to at least one inclined side of a transverse trough of said coil car.
 19. A transverse coil car having a center sill that is notched to conform to at least one transverse trough of said coil car.
 20. A transverse trough coil car having first and second troughs extending thereacross; said first and second troughs each having a pair of first and second opposed slope sheets; there being a straight-through center sill having a top cover plate; and at least one of: (a) said slope sheets terminating at an upward edge that conforms to said top cover plate; and (b) said first slope sheet of said first trough lying in a first plane; said second slope sheet of said second trough lying in a second plane, said first and second planes being upwardly inclined toward each other to intersect at a line of intersection above said center sill; and an upper edge of said first slope sheet of said first trough and a corresponding upper edge of said second slope sheet of said second trough being truncated lower than said line of intersection. 